Low spill high flow quick coupling valve assembly

ABSTRACT

A high flow low spill quick coupling valve assembly (40) is used to connect to pressurized large diameter fluid lines. The valve assembly includes a female coupling (44) and a male coupling (42), each of which defines a fluid passageway. Both male and female coupling valves are fluid pressure balanced to minimize the connecting force used to lock the valve assembly and the disconnecting force used to unlock the valve assembly. The fluid spillage or leakage is minimized. All spring members (80, 104) in the valve assembly are isolated from the fluid passageways. The valve assembly also includes a plurality of static seals between inner and outer bodies of the male coupling and between an inner body and a fluid conduit adaptor of the female coupling, or between the end surfaces of the inner and outer bodies of the male coupling and between the end surfaces of the inner body and the fluid conduit adaptor of the female coupling. The static seals are deformed, once the coupling valve assembly is assembled, to form a seal. Preferably, the entire valve assembly is made of plastic material except for the spring members which are disposed outside the fluid passageways.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a 371 of PCT/US96/00209, filed Jan. 5, 1996 and aCIP of 08/728,403, filed Oct. 9, 1996, which is a continuationapplication of U.S. Ser. No. 08/369,490 filed Jan. 6, 1995.

FIELD OF THE INVENTION

The present invention relates to a quick coupling valve assembly, moreparticularly, to a low spill high flow quick coupling valve assembly.

BACKGROUND OF THE INVENTION

Generally, the invention relates to coupling valve assemblies of thequick connect type.

Various types of quick coupling valve assemblies are known and disclosedin the art, such as a quick connection coupling valve assembly disclosedin the U.S. Pat. No. 5,316,041, issued to Patrick J. Ramacier, Jr. andDavid W. Meyer. The conventional coupling valve assemblies are generallyused in low internal fluid pressure, small diameter fluid lines. Theinternal fluid pressure is applied to a full cross-section valve membersof the coupling valve assembly. For example, the '041 patent discloses avalve assembly which includes a poppet valve member in each of thefemale and male couplings. The internal fluid pressure is applied to afull cross-section both female and male of the poppet valve members. Toengage/disengage the male coupling with/from the female coupling, alarge connection force is required to overcome the internal fluidpressure.

In high internal pressure, large diameter fluid lines, it requires anextremely large connection force to overcome the high internal fluidpressure. The present invention solves this problem by minimizing thecross-sectional area of the valve members on which the fluid flow acts.Accordingly, the valve members, of male and female couplings, aresubstantially pressure balanced so that the acting force is dramaticallyreduced.

In addition, spring members which are utilized in the conventionalcoupling assemblies are exposed to fluid passageways. The presentinvention encloses spring members so that the spring members are notexposed to fluid passageways.

In addition, in the fluid dispensing industry, there are other concerns,such as the cost of the coupling valve assembly. The present inventionminimizes the cost by providing a coupling valve assembly made from aminimal number of parts.

There is also a need for coupling valve assemblies which can be reusedwith a variety of connections. The present invention provides anon-disposable coupling valve assembly which can be utilized with avariety of fluid conduit adaptors.

The present invention provides a coupling valve assembly which solvesthese and other problems associated with existing coupling valveassemblies.

SUMMARY OF THE INVENTION

The present invention relates to a quick coupling valve assembly, moreparticularly, to a low spill high flow quick coupling valve assembly.

In one embodiment, a coupling valve assembly generally in accordancewith the present invention comprises:

a female coupling including:

a female coupling outer body having a front end and a back end;

a female coupling inner body, having a front end and a back end, beingretained in the female coupling outer body;

a female coupling slide valve being reciprocally received between thefemale coupling outer body and the female coupling inner body forreciprocal movement along a longitudinal axis of the coupling valveassembly;

a female coupling spring being disposed between the female couplinginner and outer bodies, the female coupling slide valve being normallybiased toward the front end of the outer body by the female couplingspring;

the female coupling inner body defining a female coupling fluidpassageway therethrough, the female coupling inner body including afluid port in a circumferential wall of the female coupling inner bodyproximate the front end of the female coupling inner body, the femalecoupling slide valve and the female coupling inner body forming a fluidtight seal sealing off the fluid port when the female coupling slidevalve is biased to the front end of the female coupling, whereby thefemale coupling slide valve normally closes the fluid port so that thefemale coupling is normally closed and prohibits fluid flowtherethrough, the female coupling spring being isolated from the femalecoupling fluid passageway;

a male coupling, including:

a male coupling outer body having a front end and a back end;

a male coupling inner body, having a front end a back end, beingretained in the male coupling outer body;

a male coupling slide valve, having a front end portion and a back endportion, being reciprocally received in the male coupling inner body forreciprocal movement along the longitudinal axis of the coupling valveassembly;

a male coupling spring being disposed inside the male coupling slidevalve between the front end portion of the male coupling slide valve andthe back end of the male coupling inner body, the male coupling slidevalve being normally biased toward the front end of the male couplingouter body by the male coupling spring;

a male coupling insert seat retaining the male coupling slide valve inthe male coupling outer body;

a male coupling fluid passageway being defined between the male couplingouter body and the male coupling inner body, the front end portion ofthe male coupling slide valve and the front end of the male couplingouter body forming a fluid tight seal when the male coupling slide valveis normally biased to the front end of the male coupling, whereby themale coupling slide valve normally engages with the front end of themale coupling outer body so that the male coupling is normally closed,the male coupling spring being isolated from the male coupling fluidpassageway;

a clip assembly being disposed proximate the front end of the femalecoupling for releasably locking the male coupling in the femalecoupling, so that the female coupling fluid passageway is in fluidcommunication with the male coupling fluid passageway; and

a vent conduit passing through the male coupling inner body and the malecoupling outer body to vent pressure between inside of the couplingvalve assembly and outside of the coupling valve assembly so thatpressure between inside and outside of the coupling valve assembly isequalized.

Further in one embodiment, a pressure balancing feature is built in thevalve assembly in both half sides of the coupling valve assembly. Inparticular, the internal fluid pressure only applies onto a smallcross-section of the valve members so that the connecting force isdramatically reduced. The separating force is also dramatically reduced.In addition, it prevents the risk where the male coupling member fliesout of the female coupling member. One advantage of having the pressurebalance features is that it allows for the use of an inexpensivelightweight, transversely mounted, molded plastic clip assembly which isobvious to the user as to how it operates. Moreover, the clip assemblyprovides audible feedback to the user informing the user when the femalecoupling and the male coupling are releasably locked together by theclip assembly.

Still in one embodiment, the female and male coupling springs are notexposed to the female and male coupling fluid passageways. The internalair pressure in the coupling valve assembly resulting from thereciprocal movement of the male and female coupling slide valves isequalized to the external pressure outside the coupling valve assembly.Thus, the male coupling can be easily inserted and locked in the femalecoupling.

Further in one embodiment, upon locking the male coupling into thefemale coupling, the female coupling inner body and male coupling slidevalve engage one another and the female coupling slide valve and themale coupling outer body engage one another. Accordingly, the femalecoupling slide valve is pushed away from the fluid port of the femalecoupling inner body, and the male coupling slide valve is pushed awayfrom the front end of the male coupling outer body. The male and femalecoupling passageways are thus open and in fluid communication with eachother.

Still in one embodiment, the front end portion of the male couplingslide valve has a recessed portion for receiving the front end of thefemale coupling inner body. A fluid sealing member is disposed on anouter circumferential surface of the female coupling inner bodyproximate the front end of the female coupling inner body. When the malecoupling is engaged with the female coupling at a pre-locking position,the fluid sealing member forms a fluid tight seal between the front endof the female coupling inner body and the inner side walls of therecessed portion. The fluid passageways are shut off when the male andfemale couplings are engaged the pre-locking position. Therefore, fluidspillage is minimized between the coupling male member and the couplingfemale member.

Yet in one embodiment, the clip assembly includes a clip member beingtransversely disposed relative to the female coupling, and a springmember being disposed between a top portion of the clip member and anouter surface of the female coupling outer body, a bottom portion of theclip member being normally disposed inside the female coupling outerbody and being biased toward outside the female coupling outer body. Thefront end of the male coupling outer body is tapered inwardly, so thatwhen the front end of the male coupling is inserted into the femalecoupling, the bottom portion of the clip member is biased to outside thefemale coupling outer body. Further, the bottom portion of the clipmember is biased to outside the female coupling outer body when thefemale coupling and the male coupling are engaged in the pre-lockingposition.

Further in one embodiment, a female coupling fluid conduit adaptor ismounted onto the back end of the female coupling outer body forconducting fluid therethrough, and a male coupling fluid conduit adaptoris mounted onto the back end of the male coupling outer body forconducting fluid therethrough.

Still in one embodiment, the female coupling fluid conduit adaptor andthe male coupling fluid conduit adaptor are detachably, threadedlymounted in the female coupling outer body and male coupling outer body,respectively. The adaptors are configured in such a manner as to fit inboth male and female bodies. Accordingly, the fluid conduit adaptors canbe replaceable according to different sizes of fluid line connections.By having such a replacement feature, the coupling valve assembly can bereadily adapted to or reused with different types of fluid lineconnections.

Yet in one embodiment, the back end of the male coupling inner body hasa conical shape, so that fluid smoothly flows between the male couplingfluid passageway and the male coupling fluid conduit adaptor.

Further in one embodiment, the fluid sealing member is an O-ring or aquad-ring. In one embodiment, the quad-ring is lubricated.

Still in one embodiment, the male coupling insert seat also allows toinclude an internal quad ring groove in the design as a molded feature.This groove must otherwise be machined requiring a costly secondoperation. More importantly, when leaving a thick section as would berequired for machining of the groove in a molded plastic part, thereoften forms shrinks and porosity in the form of air pockets just belowthe surface. These pockets would then be exposed when machining thegroove and thus a leakage path would be created. One embodiment of thepresent invention overcome this costly and potentially catastrophicshortcoming with the use of the seat insert.

In one embodiment, a coupling valve assembly comprises:

a female coupling defining a female coupling fluid passageway, thefemale coupling member including a female coupling valve which isnormally biased into a closed position by a female coupling spring so asto close the female coupling fluid passageway, the female coupling valveincluding a female coupling slide valve and a female coupling innerbody, the female coupling slide valve being disposed in the femalecoupling for reciprocal movement along a longitudinal axis of thecoupling valve assembly, the female coupling spring being isolated fromthe female coupling fluid passageway;

a male coupling defining a male coupling fluid passageway, the malecoupling including a male coupling valve which is normally biased into aclosed position by a male coupling spring so as to close the malecoupling fluid passageway, the male coupling valve including a malecoupling slide valve, a male coupling outer body, and a male couplinginner body, the male coupling slide valve being disposed in the malecoupling for reciprocal movement along the longitudinal axis of thecoupling valve assembly, the male coupling spring being isolated fromthe male coupling fluid passageway;

the female coupling inner body engaging with the male coupling slidevalve and the male coupling outer body engaging with the female couplingslide valve so as to open the fluid passageways;

a clip assembly having a locking member to lock the male coupling in thefemale coupling and having an unlocking member to unlock the malecoupling from the female coupling wherein the fluid passageways areclosed; and

a vent conduit passing through the male coupling inner body and the malecoupling outer body to vent air pressure between inside of the couplingvalve assembly and outside of the coupling valve assembly so that theair pressure between the inside and outside of the coupling valveassembly is equalized.

A coupling valve assembly comprises:

a female coupling defining a female coupling fluid passageway, thefemale coupling member including a female coupling valve which isnormally biased into a closed position by a female coupling spring so asto close the female coupling fluid passageway, the female coupling valveincluding a female coupling slide valve and a female coupling innerbody, the female coupling slide valve being disposed in the femalecoupling for reciprocal movement along a longitudinal axis of thecoupling valve assembly, the female coupling spring being isolated fromthe female coupling fluid passageway;

a male coupling defining a male coupling fluid passageway, the malecoupling including a male coupling valve which is normally biased into aclosed position by a male coupling spring so as to close the malecoupling fluid passageway, the male coupling valve including a malecoupling slide valve, a male coupling outer body, and a male couplinginner body, the male coupling slide valve being disposed in the malecoupling for reciprocal movement along the longitudinal axis of thecoupling valve assembly, the male coupling spring being isolated fromthe male coupling fluid passageway;

the female coupling inner body engaging with the male coupling slidevalve and the male coupling outer body engaging with the female couplingslide valve so as to open the fluid passageways;

a clip assembly having a locking member to lock the male coupling in thefemale coupling and having an unlocking member to unlock the malecoupling from the female coupling wherein the fluid passageways areclosed;

a vent conduit passing through the male coupling inner body and the malecoupling outer body to vent air pressure between inside of the couplingvalve assembly and outside of the coupling valve assembly so that theair pressure between the inside and outside of the coupling valveassembly is equalized; and

fluid pressure balance means for reducing fluid pressurized area on themale and female coupling slide valves.

Still in one embodiment, the fluid pressure balance means includes afirst sealing member which seals between the male coupling inner bodyand the male coupling slide valve, a second sealing member which sealsbetween the female coupling inner body and the male coupling slidevalve, a third sealing member which seals between the female couplingslide valve and the male coupling outer body, and a fourth sealingmember which seals between the female coupling inner body and the femalecoupling side valve.

Yet in one embodiment, the sealing members are either an O-ring or aquad-ring.

In one embodiment, a coupling valve assembly, comprising:

a female coupling defining a female coupling fluid passagewaytherethrough, the female coupling including a female valve which isnormally biased into a closed position by a female coupling spring so asto close the female coupling fluid passageway, the female couplingspring being isolated from the female coupling fluid passageway;

a male coupling defining a male coupling fluid passageway therethrough,the male coupling including a male valve which is normally biased into aclosed position by a male coupling spring so as to close the malecoupling fluid passageway, the male coupling spring being isolated fromthe male coupling fluid passageway;

means for locking the male coupling in the female coupling so as to openthe fluid passageways;

means for unlocking the male and female couplings so as to close thefluid passageways; and

vent means for equalizing internal air pressure of the coupling valveassembly with external air pressure outside the coupling valve assembly.

Still in one embodiment, the coupling valve assembly further comprisesmeans for sealing the male and female couplings at a pre-lockingposition, whereby the fluid passageways are closed. Therefore, fluidspillage is minimized after unlocking.

One method for connecting/disconnecting a coupling valve assembly,comprises the steps of:

providing a female coupling defining a female coupling fluid passageway,the female coupling including a female valve which is normally biasedinto a closed position by a female coupling spring so as to close thefemale passageway, the female coupling spring being isolated from thefemale coupling fluid passageway;

providing a male coupling defining a male coupling fluid passageway, themale coupling including a male valve which is normally biased into aclosed position by a male coupling spring so as to close the malepassageway, the male coupling spring being isolated from the malecoupling fluid passageway;

inserting the male coupling into the female coupling;

engaging the male coupling with the female coupling into a pre-lockingposition wherein the fluid passageways are closed;

locking the male and female couplings in a locking position wherein thefluid passageways are open;

venting internal air pressure inside of the valve assembly to theoutside of the valve assembly;

unlocking the male and female couplings by pressing a clip assembly, themale and female couplings being returned to the pre-locking positionupon being unlocked, the fluid passageways being closed, whereby fluidspillage upon unlocking is minimized; and

separating the male coupling from the female coupling.

Still in one embodiment, a plurality of 0-rings, functioning as staticseals, are retained in the grooves disposed on the outer wall of theinner body of the male coupling and in the groove disposed on the outerwall of the inner body of the female coupling, respectively.

In a second embodiment, static seals are integrally molded with theouter wall of the inner body of the male coupling and with the outerwall of the inner body of the female coupling, respectively. Theintegral static seals can be of various shapes.

In yet another embodiment, static seals are formed between the endsurfaces of a fluid conduit adaptor and the inner body of the femalecoupling, and between the end surfaces of the outer body and inner bodyof the male coupling. The end surfaces are made from ductile, malleable,and low tensile plastic materials, such as fluoropolymer (e.g. Teflon™).In one embodiment, the substantially entire coupling is made of thismaterial. In a second embodiment, the end surfaces are made from aplastic material which is more ductile, more malleable, and of lowertensile strength than the rest of the coupling body. In yet anotherembodiment, various inner portions of the coupling are made from aplastic material which is more ductile, more malleable, and of lowertensile strength than various outer portions of the coupling.Accordingly, when the coupling valve assembly is assembled, the endsurfaces are thus deformed to form a seal between the inner body andouter body of the male coupling and a seal between the inner body andfluid conduit adaptor of the female coupling.

These and various other advantages and features of novelty whichcharacterize the invention are pointed out with particularity in theclaims annexed hereto and forming a part hereof. However, for a betterunderstanding of the invention, its advantages, and objects obtained byits use, reference should be made to the drawings which form a furtherpart hereof, and to the accompanying descriptive matter, in which thereis illustrated and described a preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, in which like reference numerals and letters generallyindicate corresponding parts throughout the following several views:

FIG. 1 is a longitudinal cross-sectional view of an embodiment of acoupling valve assembly in accordance with the principles of the presentinvention, wherein a male coupling is separated from a female coupling.

FIG. 2 is a longitudinal cross-sectional view of the coupling valveassembly, wherein the male coupling is engaged with the female couplingin a pre-locking position.

FIG. 3 is a longitudinal cross-sectional view of the coupling valveassembly, wherein the male coupling is engaged with the female couplingin a locking position.

FIG. 4 is a top plane view of an outer body of the female coupling.

FIG. 5 is a front end view of the outer body of the female coupling.

FIG. 6 is a side view of the outer body of the female coupling.

FIG. 7 is a longitudinal cross-sectional view of the outer body of thefemale coupling.

FIG. 8 is a side view of an inner body of the female coupling.

FIG. 9 is a longitudinal cross-sectional view of the inner body of thefemale coupling.

FIG. 10 is a front end view of the inner body of the female coupling.

FIG. 11 is a side view of an outer body of the male coupling.

FIG. 12 is a longitudinal cross-sectional view of the outer body of themale coupling.

FIG. 13 is a back end view of the outer body of the male coupling.

FIG. 14 is a side view of an inner body of the male coupling.

FIG. 15 is a longitudinal cross-sectional view of the inner body of themale coupling.

FIG. 16 is a front end view of the inner body of the male coupling.

FIG. 17 is a side view of a female coupling slide valve of the femalecoupling.

FIG. 18 is a longitudinal cross-sectional view of the female couplingslide valve of the female coupling.

FIG. 19 is a back end view of the female coupling slide valve of thefemale coupling.

FIG. 20 is a side view of a male coupling slide valve of the malecoupling.

FIG. 21 is a longitudinal cross-sectional view of the male couplingslide valve of the male coupling.

FIG. 22 is a back end view of the male coupling slide valve of the malecoupling.

FIG. 23 is a top plane view of a clip assembly.

FIG. 24 is a front end view of the clip assembly.

FIG. 25 is a longitudinal cross-sectional view of the clip assembly.

FIG. 26 is a side view of an insert seat of the male coupling.

FIG. 27 is a longitudinal cross-sectional view of the insert seat of themale coupling.

FIG. 28 is a back end view of the insert seat of the male coupling.

FIG. 29 is a longitudinal cross-sectional view of a fluid conduitadaptor attached to both the male and female couplings.

FIG. 30 is a front view of the fluid conduit adaptor.

FIG. 31 is an enlarged partial cross-sectional view of a quad-ring whichis disposed in the coupling valve assembly.

FIG. 32 is an enlarged partial cross-sectional view of a secondembodiment of static seals which are integrally molded with the innerbody of the couplings.

FIG. 33 is an enlarged partial cross-sectional view of the secondembodiment of static seals of FIG. 32 which are in an interference fitwith the outer body of the couplings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings in details, wherein like numerals identifysimilar elements throughout, FIGS. 1 to 3 show an embodiment of acoupling valve assembly 40, generally in accordance with the principlesof the invention, being disposed in a separating position, a pre-lockingposition, and a locking position, respectively.

The coupling valve assembly 40 includes a male coupling 42 and a femalecoupling 44. The male coupling 42 is disengaged from the female coupling44 in the separating position as shown in FIG. 1. The male coupling 42is inserted in the female coupling 44 in the pre-locking position asshown in FIG. 2 and in the locking position as shown in FIG. 3.

For purposes of explanation, the parts used in the female coupling willinclude the designator "female coupling", such as female couplingspring, etc. The part used in the male coupling will include thedesignator "male coupling" such as male coupling spring, etc.

As shown in FIGS. 1-3, the female coupling 44 includes an outer body 46which is shown in FIGS. 4-7 in details. The outer body 46 has a tubularshape and has an front end 48 and a back end 50. The front end 48receives the male coupling 42. The back end 50 receives a fluid conduitadaptor 52 (see FIGS. 29-30).

The fluid conduit adaptor 52 is detachably mounted on the back end 50.It is appreciated that the fluid conduit adaptor 52 can be attached tothe back end 50 by other means such as molding, or mounting by mountingdevices, etc. Accordingly, the fluid conduit adaptor 52 is replaceableaccording to different sizes of fluid line connections (not shown).Thus, the coupling valve assembly 40 can be reused with a variety ofconnections. The fluid conduit connector 52 can be used with both thefemale and male couplings to minimize the parts.

Further in FIGS. 4-7, a slot 54 transversely passes through the outerbody 46 proximate the front end 48 of the female coupling 44. Acircumferential wall 56 is disposed around the slot 54 and forms arecessed portion 58 between the slot 54 and the wall 56.

As shown in FIGS. 1-3, a clip assembly 60 passes through the slot 54.The clip assembly 60 is shown in FIGS. 23-25 in detail. The clipassembly 60 includes a top horizontal tab portion 62 and a verticalcircular portion 64. The vertical circular portion 64 is molded with thetop horizontal tab portion 62. The vertical circular portion 64 isdisposed in the slot 54. A spring 66 is disposed between the recessedportion 58 and the top horizontal tab portion 62. Accordingly, the clipassembly 60 is reciprocally movable in the slot 54. In addition, theclip assembly 60 is normally biased toward the top of the femalecoupling 44, and a bottom part 65 of the vertical circular portion 64 isbiased to the inside of the outer body 46. The bottom part 65 of thevertical circular portion 64 is pushed out of the outer body 46 bypressing the clip assembly 60 downwardly.

Further in FIGS. 1-3, the female coupling 44 includes an inner body 68.The inner body 68 is retained in the outer body 46. The inner body 68 isshown in detail in FIGS. 8-10. The inner body 68 has a front end 70 anda back end 72. A fluid passageway 74 passes through the inner body 68between the back end 72 and a fluid port 76 in a circumferential wall ofthe female coupling inner body 68 proximate the front end 70.

Still in FIGS. 1-3, the female coupling 44 includes a slide valve 78 anda spring 80. The slide valve 78 is reciprocally received between theouter body 46 and the inner body 68 for reciprocal movement along alongitudinal axis A-A' of the coupling valve assembly 40. The slidevalve 78 is normally biased toward the front end 48 of the outer body 46by the spring 80. A projection 82 stops the forward movement of theslide valve 78. FIGS. 17-19 show the slide valve 78 in detail. Thespring 80 is disposed between a back side 84 of the slide valve 80 and atransverse flange 86 of the inner body 68 which is disposed outside theinner body 68. Accordingly, the spring 80 is not exposed to the fluidpassageway 74.

The slide valve 78 is normally biased to the front end 70 of the innerbody 68 by the spring 80. The fluid port 76 is shut off by the slidevalve 78, so that the fluid passageway 74 is closed at the front end 48of the female coupling 44. When the slide valve 78 is pushed backwardand away from the front end 70 and the fluid port 76, the fluidpassageway 74 is open.

In FIGS. 1-3, the male coupling 42 includes an outer body 88. The outerbody 88 is shown in FIGS. 11-13 in detail. The outer body 88 has atubular shape. The outer body 88 has a tapered front end 90 and a backend 92. The back end 92 also receives the fluid conduit adaptor 52 asdescribed above. A circumferential recessed portion 94 is disposedproximate the middle of the outer body 88. The circumferential recessedportion 94 receives and engages with the bottom part 65 of the verticalcircular portion 64. Accordingly, the male coupling 42 is locked in thefemale coupling 44, as shown in FIG. 2.

Further as shown in FIGS. 11-13, the male coupling outer body 88 hasventing holes 89,91.

Back to FIGS. 1-3, the male coupling 42 includes an inner body 96. Theinner body 96 is retained in the outer body 88. The inner body 96 isshown in FIGS. 14-16 in detail. The inner body 96 has a front end 98 anda back end 100. The back end 100 has a conical shape. The male coupling42 further includes a slide valve 102 and a spring 104. The slide valve102 is biased toward the front end 90 of the male coupling 42 by thespring 104. Thus, the slide valve 102 is reciprocally received in theinner body 96 for reciprocal movement along the longitudinal axis A-A'of the valve assembly 40. The spring 104 is disposed between a back side106 of the slide valve 102 and the back end 100 of the inner body 96.Accordingly, a front end portion 108 of the slide valve 102 biasedlyprojects out of the inner body 96 to the front end 90 of the malecoupling 42.

Further in FIGS. 14-16, the inner body 96 includes a vent conduit 110.The vent conduit 110 vertically passes through the body of the innerbody 96. The vent conduit 110 is in communication with the venting holes89,91 on the outer body 88 (see FIGS. 1-3). Accordingly, the back sideof the slide valve in the male coupling is vented and thus is equalizedto the pressure outside of the coupling valve assembly 40. Therefore,this pressure equalization makes it easier to couple the male and femalecoupling halves when the slide valve 102 is biasedly pushed toward backend 92 of the male coupling 42.

Further, and much more significantly, a pressure balance is achieved ineach coupling half and between the two halves when coupled. This isaccomplished by the significant reduction of effective area upon whichthe fluid pressure acts to create a force which opposes the couplingaction. The valve assembly connection force is dramatically reduced.Accordingly, the applied force required to couple the coupling halvesand thus the force acting on the clip assembly which locks the twocoupling halves is substantially reduced. The clip assembly 60 can thusbe made of a lightweight, plastic material.

The slide valve 102 is shown in FIGS. 20-22 in detail. A recessedportion 112 is disposed at the front end portion 108 of the slide valve102. The front end 70 of the female coupling inner body 68 is receivedin the recessed portion 112 (see FIGS. 2-3). A fluid sealing member 114,which is retained in the outer wall of the inner body 68 proximate thefront end 70, seals the gap between the inner wall of the recessedportion 112 and the outer wall of the inner body 68. Thus, the fluid isstopped from moving into the recessed portion 112. As shown in FIGS.1-3, the male coupling spring 104 is not exposed to the fluid passageway132. A fluid sealing member 134 is retained in the outer wall of themale coupling slide valve 102 proximate a back end portion 136 thereof.The fluid sealing member 134 seals the gap between the outer wall of themale coupling slide valve 102 and the inner wall of the male couplinginner body 96. Thus, no fluid can flow into the inner body 96 of themale coupling 42. As a result, the male coupling slide valve 102 ispressure balanced in the internal fluid flow.

In addition, a fluid sealing member 116 is retained in the outer wall ofthe inner body 68 proximate the front end 70 behind the fluid sealingmember 114. The fluid sealing member 116 seals the gap between the outerwall of the inner body 68 and the inner wall of the female couplingslide valve 78 (see FIGS. 2-3).

The fluid sealing members 114, 116 are resilient sealing members, suchas a quad-ring, as generally shown in FIG. 31 in an enlarged view. It isappreciated that other types of sealing members, such as O-rings, U-cupseals, etc., can be used to address various design objectives such asfriction, lubricant use, leakage, life, etc.

Further in FIG. 21, a hole 118 is disposed proximate the center of thefront end portion 108 of the male coupling slide valve 102. The hole 118equalizes the pressure between the front end 70 of the female couplinginner body 68 and the front end portion 108 of the male coupling slidevalve 102 (see FIGS. 1 and 2) to outside the valve assembly 40 throughthe vent conduit 110.

Further in FIGS. 1-3, the male coupling 42 further includes an insertseat 120. The insert seat 120 is retained in the male coupling outerbody 88. The insert seat 120 is shown in FIGS. 26-28 in detail. Theinsert seat 120 has a front end 122 and a back end 124. The front end122 of the insert seat 120 and the front end 90 of the outer body 88form an internal sealing groove for receiving a sealing member. In FIGS.1-3, a fluid sealing member 126 is retained between the front end 122 ofthe insert seat 120 and the front end 90 of the outer body 88. The fluidsealing member 126 seals between the front end outer side wall of thefemale coupling slide valve 78 and the front end inner side wall of themale coupling outer body. Thus, the fluid is stopped from moving to therest of the cross-section of the female coupling slide valve. Further inFIGS. 1-3, the female coupling spring 80 is not exposed to the fluidpassageway 74. A fluid sealing member 138 is retained in the outer wallof the female coupling inner body 68 proximate the middle of the femalecoupling inner body 68. The fluid sealing member 138 seals the gapbetween the outer wall of the female coupling inner body 68 and theinner wall of the female coupling slide valve 78. Thus, no fluid canflow into the inner body 68 of the female coupling 44. As a result, thefemale coupling slide valve 78 is pressure balanced in the internalfluid flow.

The fluid sealing member 126 is a resilient sealing member, such as aquad-ring as shown in FIG. 31. Other types of fluid sealing members,such as an O-ring, U-cups, etc. can replace the quad-ring to achievevarious design objectives. Thus, the fluid spillage is minimized.

Still in FIG. 1, the male coupling slide valve 102 is biased to thefront end 122 of the insert seat 120. A circumferential flange 128 (seeFIGS. 20-21) which is disposed proximate the front end portion 108 ofthe slide valve is engaged with a circumferential shoulder 130 (seeFIGS. 26-27) which is disposed proximate the front end 122 of the insertseat 120. The shoulder 130 of the insert seat 120 engages with theflange 128 to stop the male coupling slide valve 102 forward travel outof the male coupling 42 when the slide valve 102 is biased toward thefront end 90 of the male coupling outer body 88 by the male couplingspring 104.

In FIGS. 1-3, a fluid passageway 132 is generally defined between theouter wall of the inner body 96, and the inner wall of the outer body88. When the front end portion 108 of the male coupling slide valve 102is engaged to the front end 90 of the male coupling outer body 88, thefluid sealing member seals the gap therebetween. Accordingly, the fluidpassageway 132 is shut off, and no fluid can flow out of the front end90 of the outer body 88. When the male coupling slide valve 102 isbiased toward the back end 92 of the outer body 88, the front endportion 108 of the male coupling slide valve 102 is disengaged from thefront end 90 of the male coupling outer body 88. Accordingly, the fluidpassageway 132 is open as shown in FIG. 3.

As described above, the back end 100 of the inner body 96 has a conicalshape. Thus, the fluid smoothly flows from the fluid passageway 132 tothe fluid conduit adaptor 52.

In operation, the male coupling 42 is inserted into the female coupling44 (shown from FIG. 1 to FIG. 2). The tapered front end 90 of the malecoupling outer body 88 pushes the bottom part 65 of the verticalcircular portion 64 of the clip assembly 60 out of the female couplingouter body 46. The front end 70 of the inner body 68 is received in therecessed portion 112 of the male coupling slide valve 102. At this time,the valve assembly 40 is at a pre-locking position (see FIG. 2), wherethe male coupling slide valve 102 is started to be pushed away from thefront end 90 of the male coupling outer body 88. The male couplingspring 104 is started to be compressed. The flange 128 of the front endportion 108 of the male coupling slide valve 102 is started to bedisengaged from the front end 90 of the outer body 88 and the fluidsealing member 126. The fluid passageway 132 is still shut off by theengagement between the fluid sealing member 126 and the front endportion 108 of the male coupling slide valve 102. Therefore, fluidspillage or leakage is minimized between the male coupling 42 and thefemale coupling 44 at the pre-locking position.

At the pre-locking position, the outer wall of the male coupling outerbody 88 and the inner wall of the female coupling outer body 46 tightlyfit with each other. In addition, the upwardly biased vertical circularportion 64 of the clip assembly 60 helps the male coupling 42 fit withthe female coupling 44 at the pre-locking position. Further, thecoupling halves are now pressure balanced, that is there is little orsubstantially no effective pressure area exposed to create oppositionforce to continued operation of the valve assembly.

Further pushing the male coupling 42 into the female coupling 44, thefemale coupling inner body 68 is engaged with the male coupling slidevalve 102 and pushes the male coupling slide valve 102 toward the backend 92 of the male coupling outer body 88. Meanwhile, the male couplingouter body 88 is engaged with the female coupling slide valve 78 andpushes the female coupling slide valve 78 toward the back end 50 of thefemale coupling outer body 46. Accordingly, in the male coupling 42, thefront end portion 108 of the male coupling slide valve 102 is pushedaway from the front end 90 of the male coupling outer body 88 and thefluid sealing member 126, so that the fluid passageway 132 is open tothe female coupling 44. In the female coupling 44, the female couplingslide valve 78 is pushed away from the fluid port 76 so that the fluidpassageway 74 is open to the male coupling 42. At this time, thecoupling valve assembly 40 is in a locking position (see FIG. 3). Thefluid passageway 74 and the fluid passageway 132 are in fluidcommunication.

In the locking position, the bottom part 65 of the vertical circularportion 64 of the clip assembly 60 is received and engaged in thecircumferential recessed portion 94 of the male coupling outer body 88.Thus, the male coupling 42 and the female coupling 44 are lockedtogether.

In the locking process, the male coupling spring 104 and the femalecoupling spring 80 are compressed. The internal pressure of the valveassembly 40 is balanced and the male slide valve is vented through thevent conduit 110 and the venting holes 89,91. This pressure balancemakes the locking process much easier and minimizes the increase incoupling force as a function of increasing fluid pressure.

To unlock the valve assembly 40, the top tab portion 62 of the clipassembly 60 is pushed downwardly where the spring 66 is compressed.Accordingly, the bottom part 65 of the vertical circular portion 64 ofthe clip assembly 60 is disengaged from the circumferential recessedportion 94 of the male coupling outer body 88. In the female coupling44, the female coupling slide valve 78 is biased to the front end 48 ofthe female coupling outer body 46 by the female coupling spring 80. Thefluid port 76 is then closed by the engagement of the female couplingslide valve 78 and the front end 70 of the female coupling inner body68. Thus, the fluid passageway 74 is cut off. Meanwhile, in the malecoupling 42, the male coupling slide valve 102 is biased to the frontend 90 of the male coupling outer body 88 by the male coupling spring104. The fluid passageway 132 is then shut off.

At this time, the valve assembly 40 is returned to the pre-lockingposition. The front end 70 of the female coupling inner body 68 is stillengaged with the recessed portion 112 of the male coupling slide valve102.

During the unlocking process, the fluid sealing members 114, 116, 126,the front end 70 of the coupling inner body 68, the female slide valve78, and the front end portion 108 of the male slide valve 102 preventthe fluid from leaking or spilling out of the fluid passageways 74, 132into the gap between the front end of 70 the female coupling outer body68 and the front end 90 of the male coupling outer body 88.

Next, as shown in FIG. 1, the male coupling 42 and the female coupling44 are separated from each other by pulling the male coupling 42 out ofthe female coupling 44. At this time, the male coupling slide valve 102is further biased toward the front end 90 of the male coupling outerbody 88 and is finally stopped by the engagement of the flange 128 ofthe male coupling slide valve 102 and the shoulder 130 of the insertseat 120.

In both the locking position and the pre-locking position, the malecoupling 42 and the female coupling 44 are free to rotate relative toone another due to their tubular shapes as shown in the drawings.

Further, all the parts of the valve assembly 40, except the malecoupling spring 104, the female coupling spring 80, and the spring 66 ofthe clip assembly 60, are made of plastic and/or elastomeric materials.It is appreciated that any other materials, such as metals, etc., can bealso used.

As also shown in FIG. 1, a plurality of O-rings 200,202,204, functioningas static seals, are retained in the corresponding grooves 206,208disposed on the outer wall 212 of the inner body 96 of the male coupling42 and in the groove 210 disposed on the outer wall 214 of the innerbody 68 of the female coupling 44, respectively. The O-rings 200,202,204are deformed once the coupling valve assembly 40 is assembled.

In a second embodiment, the O-rings 200,202,204 are replaced by staticseals 216 which are integrally molded with the outer wall 212 of theinner body 96 of the male coupling 42 (shown in FIG. 32), and with theouter wall 214 of the inner body 68 of the female coupling 44 (notshown), respectively. The integral static seals 216 can be of variousshapes. In FIG. 33, two of the static seals 216 are deformed between theinner body 96 and outer body 88 of the male coupling 42 when thecoupling valve assembly is assembled. Another static seal 216 isdeformed between the inner body 68 and the fluid conduit adaptor 52 ofthe female coupling 44 when the coupling valve assembly 40 is assembled.The static seals 216 thus form a seal between the inner body 96 and theouter body 88 and between the inner body 68 and the fluid conduitadaptor 52, respectively, when so deformed. Since the seals 216 do notmove any more once the coupling valve assembly 40 is assembled, theseseals 216 are often referred to as "static" seals.

Alternatively, the static seals can be formed between end surfaces of afluid conduit adaptor 52 and the inner body 68 of the female coupling44, and between the end surfaces of the outer body 88 and inner body 96of the male coupling 42. The static seals are made from ductile,malleable, and low tensile plastic materials, such as fluoropolymer(e.g. Teflon™). In one embodiment, the substantially entire coupling ismade of this material. In a second embodiment, the end surfaces are madefrom a plastic material which is more ductile, more malleable, and oflower tensile strength than the rest of the coupling body. In yetanother embodiment, various inner portions of the coupling are made froma plastic material which is more ductile, more malleable, and of lowertensile strength than various outer portions of the coupling.Accordingly, when the coupling valve assembly 40 is assembled, the endsurfaces are deformed to form a seal between the inner body 96 and theouter body 88 of the male coupling 44 and a seal between the inner body68 and the fluid conduit adaptor 52 of the female coupling 42.

It will be appreciated that alternate embodiments in keeping with theprinciples of the present invention might be utilized. It is to beunderstood, however, that even though numerous characteristics andadvantages of the invention have been set forth in the foregoingdescription, together with details of the structure and function of theinvention, the disclosure is illustrative only, and changes may be madein detail, especially in matters of shape, size and arrangement ofparts, within the principles of the invention, to the full extentindicated by the broad general meaning of the terms in which theappended claims are expressed.

What is claimed is:
 1. A coupling valve assembly, comprising:a femalecoupling, including:a female coupling outer body having a front end anda back end; a female coupling inner body, having a front end and a backend, being retained in the female coupling outer body; a female couplingslide valve being reciprocally received between the female couplingouter body and the female coupling inner body for reciprocal movementalong a longitudinal axis of the coupling valve assembly; a femalecoupling spring being disposed between the female coupling inner andouter bodies, the female coupling slide valve being normally biasedtoward the front end of the female coupling outer body by the femalecoupling spring; the female coupling inner body defining a femalecoupling fluid passageway therethrough, the female inner body includinga fluid port in a circumferential wall of the female coupling inner bodyproximate the front end of the female coupling inner body, the femalecoupling slide valve and the female coupling inner body forming a fluidtight seal sealing off the fluid port when the female coupling slidevalve is biased to the front end of the female coupling, whereby thefemale coupling slide valve normally closes the fluid port so that thefemale coupling is normally closed and prohibits fluid flowtherethrough, the female coupling spring being isolated from the femalecoupling fluid passageway; a male coupling, including:a male couplingouter body having a front end and a back end; a male coupling innerbody, having a front end a back end, being retained in the male couplingouter body; a male coupling slide valve, having a front end portion anda back end portion, being reciprocally received in the male couplinginner body for reciprocal movement along the longitudinal axis of thecoupling valve assembly; a male coupling spring being disposed insidethe male coupling slide valve between the front end portion of the malecoupling slide valve and the back end of the male coupling inner body,the male coupling slide valve being normally biased toward the front endof the male coupling outer body by the male coupling spring; a malecoupling insert seat having a front end and a back end, the malecoupling insert seat retaining the male coupling slide valve in the malecoupling outer body; a male coupling fluid passageway being definedbetween the male coupling outer body and the male coupling inner body,the front end portion of the male coupling slide valve and the front endof the male coupling outer body forming a fluid tight seal when the malecoupling slide valve is normally biased to the front end of the malecoupling, whereby the male coupling slide valve normally engages withthe front end of the male coupling outer body so that the male couplingmember is normally closed, the male coupling spring being isolated fromthe male coupling fluid passageway; a clip assembly being disposedproximate the front end of the female coupling for releasably lockingthe male coupling in the female coupling, so that the female couplingfluid passageway is in fluid communication with the male coupling fluidpassageway; and a vent conduit passing through the male coupling innerbody and the male coupling outer body to vent air pressure betweeninside of the coupling valve assembly and outside of the coupling valveassembly so that the air pressure between inside and outside of thecoupling valve assembly is equalized.
 2. A coupling valve assemblyaccording to claim 1, wherein the female and male coupling springs arenot exposed to the female and male coupling fluid passageways, theinternal pressure in the male coupling resulting from the reciprocalmovement of the male and female coupling slide valve is equalized to theexternal pressure outside the coupling valve assembly.
 3. A couplingvalve assembly according to claim 1, wherein upon locking the malecoupling into the female coupling, the female coupling inner body andthe male coupling slide valve engage one another and the female couplingslide valve and the male coupling outer body engage one another, so thatthe female coupling slide valve is pushed away from the fluid port ofthe female coupling inner body, and the male coupling slide valve ispushed away from the front end of the male coupling outer body, thepassageways are open and in fluid communication with each other.
 4. Acoupling valve assembly according to claim 1, wherein the front endportion of the male coupling slide valve has a recessed portion forreceiving the front end of the female coupling inner body, a fluidsealing member being disposed on an outer circumferential surface of thefemale coupling inner body, when the male coupling is engaged with thefemale coupling at a pre-locking position, the fluid sealing memberforming a fluid tight seal between the front end of the female couplinginner body and an inner side wall of the recessed portion, the fluidpassageways being normally closed when the male and female couplings areengaged in the pre-locking position.
 5. A coupling valve assemblyaccording to claim 1, wherein the clip assembly includes a clip memberbeing transversely disposed relative to the female coupling, and aspring member being disposed between a top portion of the clip memberand an outer surface of the female coupling outer body, a bottom portionof the clip member being normally disposed inside the female couplingouter body and being biased toward outside the female coupling outerbody, the front end of the male coupling outer body being taperedinwardly, so that when the front end of the male coupling is insertedinto the female coupling, the bottom portion of the clip member beingbiased to outside the female coupling outer body, the bottom portion ofthe clip member being biased to outside the female coupling outer bodywhen the female coupling and the male coupling are engaged in thepre-locking position.
 6. A coupling valve assembly according to claim 1,further comprising a female coupling fluid conduit adaptor which ismounted onto the back end of the female coupling outer body forconducting fluid therethrough, and a male coupling fluid conduit adaptorwhich is mounted onto the back end of the male coupling outer body forconducting fluid therethrough.
 7. A coupling valve assembly according toclaim 6, the female coupling fluid conduit adaptor and the male couplingfluid conduit adaptor are mounted in the female coupling and malecoupling, respectively, so that the fluid conduit adaptors arereplaceable according to different sizes of fluid line connections.
 8. Acoupling valve assembly according to claim 7, wherein the female andmale coupling fluid conduit adaptors are same.
 9. A coupling valveassembly according to claim 7, wherein the female and male couplingfluid conduit adaptors are detachably, threadedly mounted in the femaleand male couplings, respectively.
 10. A coupling valve assemblyaccording to claim 7, wherein the female coupling fluid passageway is influid communication with the outside of the valve assembly through thefemale coupling fluid conduit adaptor, the male coupling fluidpassageway is in fluid communication with the outside of the valveassembly through the male coupling fluid conduit adaptor.
 11. A couplingvalve assembly according to claim 10, wherein the back end of the malecoupling inner body has a conical shape, so that fluid smoothly flowsbetween the male coupling fluid passageway and the male coupling fluidconduit adaptor.
 12. A coupling valve assembly according to claim 4,wherein the fluid sealing member is a resilient flexible member.
 13. Acoupling valve assembly according to claim 12, wherein the resilientflexible member is an O-ring.
 14. A coupling valve assembly according toclaim 12, wherein the resilient flexible member is a quad-ring.
 15. Acoupling valve assembly according to claim 12, wherein the resilientflexible member is a U-cup seal.
 16. A coupling valve assembly accordingto claim 1, wherein the front end of the male coupling insert seat andthe front end of the male outer body form an internal groove to receivea resilient sealing member.
 17. A coupling valve assembly, comprising:afemale coupling defining a female coupling fluid passageway, the femalecoupling member including a female coupling valve which is normallybiased into a closed position by a female coupling spring so as to closethe female coupling fluid passageway, the female coupling valveincluding a female coupling slide valve and a female coupling innerbody, the female coupling slide valve being disposed in the femalecoupling for reciprocal movement along a longitudinal axis of thecoupling valve assembly, the female coupling spring being isolated fromthe female coupling fluid passageway; a male coupling defining a malecoupling fluid passageway, the male coupling including a male couplingvalve which is normally biased into a closed position by a male couplingspring so as to close the male coupling fluid passageway, the malecoupling valve including a male coupling slide valve, a male couplingouter body, and a male coupling inner body, the male coupling slidevalve being disposed in the male coupling for reciprocal movement alongthe longitudinal axis of the coupling valve assembly, the male couplingspring being isolated from the male coupling fluid passageway; thefemale coupling inner body engaging with the male coupling slide valveand the male coupling outer body engaging with the female coupling slidevalve so as to open the fluid passageways; a clip assembly having alocking member to lock the male coupling in the female coupling andhaving an unlocking member to unlock the male coupling from the femalecoupling wherein the fluid passageways are closed; a vent conduitpassing through the male coupling inner body and the male coupling outerbody to vent air pressure between inside of the coupling valve assemblyand outside of the coupling valve assembly so that the air pressurebetween the inside and outside of the coupling valve assembly isequalized; and fluid pressure balance means for reducing fluidpressurized area on the male and female coupling slide valves, whereinthe fluid pressure balance means includes:a first sealing member whichseals between the male coupling inner body and the male coupling slidevalve, a second sealing member which seals between the female couplinginner body and the male coupling slide valve, a third sealing memberwhich seals between the female coupling slide valve and the malecoupling outer body, and a fourth sealing member which seals between thefemale coupling inner body and the female coupling slide valve.
 18. Acoupling valve assembly, comprising:a female coupling defining a femalecoupling fluid passageway, the female coupling including a femalecoupling valve which is normally biased into a closed position by afemale coupling spring so as to close the female coupling fluidpassageway, the female coupling valve including a female slide valve, afemale coupling inner body, and a female coupling fluid conduit adaptor,the female coupling slide valve being disposed in the female couplingfor reciprocal movement along a longitudinal axis of the coupling valveassembly, the female coupling spring being isolated from the femalecoupling fluid passageway; a male coupling defining a male couplingfluid passageway, the male coupling member including a male couplingvalve which is normally biased into a closed position by a male springso as to close the male coupling fluid passageway, the male couplingvalve including a male coupling slide valve, a male coupling outer body,and a male coupling inner body, the male coupling slide valve beingdisposed in the male coupling for reciprocal movement along thelongitudinal axis of the valve assembly, the male coupling spring beingisolated from the male coupling fluid passageway; the female couplinginner body engaging with the male coupling slide valve and the malecoupling outer body engaging with the female coupling slide valve so asto open the fluid passageways; a clip assembly for locking the malecoupling in the female coupling whereby the fluid passageways are openand unlocking the male coupling from the female coupling whereby thefluid passageways are closed; and a plurality of static seals, disposedon outer walls of the male coupling inner body and female coupling innerbody, being deformed to form a seal between the male coupling inner bodyand the male coupling outer body and between the female coupling innerbody and the female coupling fluid conduit adaptor, respectively.
 19. Acoupling assembly according to claim 18, wherein the static seals areO-rings.
 20. A coupling assembly according to claim 18, wherein thestatic seals are integrally molded with the outer wall of the malecoupling inner body and the outer wall of the female coupling innerbody, respectively.
 21. A coupling assembly according to claim 18,wherein the static seals are formed between the end surfaces of the malecoupling inner body and the male coupling outer body and between the endsurfaces of the female coupling inner body and the female coupling fluidconduit adaptor, the static seals are made from more ductile, malleable,and lower tensile plastic materials than the plastic material of otherparts of the coupling assembly, so that the static seals are deformedwhen the coupling assembly is assembled so as to form a seal between theend surfaces.
 22. A coupling valve assembly according to claim 18,wherein the female coupling inner body has a front end portion having aconical back end, the male coupling inner body has a back end portionhaving a conical back end, the male and female fluid passageways have asubstantially uniform cross-section between the two conical back ends,so that a fluid flow in the passageways between the two conical backends is substantially uniform so as to prevent turbulence in thepassageways.
 23. A coupling valve assembly according to claim 18,further comprising fluid pressure balance means for reducing fluidpressurized area on the male and female coupling slide valves so as tobalance fluid pressure in the fluid passageways of the female and malecouplings when the fluid passageways are open.
 24. A coupling valveassembly according to claim 23, wherein the fluid pressure balance meansincludes:a first sealing member which seals between the male couplinginner body and the male coupling slide valve, a second sealing memberwhich seals between the female coupling inner body and the male couplingslide valve, a third sealing member which seals between the femalecoupling slide valve and the male coupling outer body, and a fourthsealing member which seals between the female coupling inner body andthe female coupling slide valve.